Unable to rotate display from landscape to portrait

This is Windows Vista desktop with Service Pack 1. Somehow my display is rotated to landscape and i am not able to change it back to normal. In order to make it portrait i went to control panel > personlization > display setting > advance settings > intel(R) graphics media accelerator driver for mobile > graphics properties > display setting. Here i guess there should be rotating angles on the right side of the small windows, right? I remember doing this on my XP systems. But in Vista i dint found any rotating angles here.

Can anyone please tell me how can i rotate my Display from Landscape to Portrait in Vista? Thank you.

The option to rotate display is same in all Windows Versions, whether it is XP or Vista you just need to press the following key combinations:

Ctrl + Alt + UP Arrow